I had, but taken out by my mechanic later on. Some told me it's a surplus item for normal cars due to the engine vibration isn't that serious (unless you had a over 300bhp+ engine that rocks ur car hard)
My sister's kancil 850 auto, rpm during idling is roughly around 2k without turning on the a/c yet.. i think it is high right? So i'm going crazy to tuning it down n manage to get 1k, i did it but it mess up...